diff --git a/services/identity/src/database.rs b/services/identity/src/database.rs
--- a/services/identity/src/database.rs
+++ b/services/identity/src/database.rs
@@ -400,6 +400,24 @@
   }
 }
 
+fn parse_user_id_attribute(
+  attribute: Option<AttributeValue>,
+) -> Result<String, DBItemError> {
+  match attribute {
+    Some(AttributeValue::S(user_id)) => Ok(user_id),
+    Some(_) => Err(DBItemError::new(
+      USERS_TABLE_PARTITION_KEY,
+      attribute,
+      DBItemAttributeError::IncorrectType,
+    )),
+    None => Err(DBItemError::new(
+      USERS_TABLE_PARTITION_KEY,
+      attribute,
+      DBItemAttributeError::Missing,
+    )),
+  }
+}
+
 #[cfg(test)]
 mod tests {
   use super::*;